Easson and Steinhilber ( 12) presented eight cases of attempted homicide, none of which was successful. Sargent ( 13) described five murderous children and hypothesized a family conspiracy in which the child who killed acted out an unconscious parental wish. The literature on homicidal aggression from the 1940s, 1950s, and early 1960s focused primarily on social and psychodynamic factors to the almost complete exclusion of neurobiologic factors ( 12– 18). Wong and Singer ( 11) found that only 7% of the 621 murderers they studied in Hong Kong were mentally ill or not guilty by reason of insanity. Gillies ( 9) found 90% of his Scottish sample of murderers to be normal and free of psychiatric diagnoses. Wolfgang ( 8), on the other hand, found that only 3% of the murderers in Philadelphia prisons were insane.
Several other authors ( 3– 7) have found murderers to have a higher prevalence of psychoses, especially the schizophrenias, than the general population. That study was, however, skewed by the fact that the sample was taken from a prison hospital. In fact, 55% were unfit to stand trial and 27% were found not guilty by reason of insanity. ( 2) found that 77% of 100 murderers received psychiatric diagnoses (schizophrenia, especially paranoid, manic-depression, psychopathic personality, and epilepsy). There is a controversy in the literature regarding the prevalence and severity of mental illness in murderers. With the exception of a single paper describing one young murderer ( 1), to the best of our knowledge all of the literature on the neuropsychiatric antecedents of homicide is retrospective. The purpose of this paper is to document the psychological, neurological, and experiential factors that consistently appeared in the cases of nine adolescents who later committed murder and to compare these adolescents with a sample of 24 delinquents who did not go on to commit violent acts within 6 years of discharge from a juvenile correction facility.
Therefore, knowledge that can help to predict and thus potentially prevent extraordinary violence is worth reporting. Murder is the most serious of all crimes.